This application claims the priority of German Patent Application Serial No. DE 100 61 343.8, filed Dec. 5, 2000, the subject matter of which is incorporated herein by reference.
The present invention relates, in general, to a lifting apparatus for implementing a rectilinear movement of a handling device, e.g., a manually-operated manipulator.
Such a vertical lifting apparatus in the manner of a lifting upright for a manually guided manipulator is known, for example, from German Pat. No. DE 43 42 716 A1. The lifting apparatus includes a longitudinal member to serve as guide part, and a lifting beam which is guided on the longitudinal member for movement in a longitudinal direction. The lifting beam has a lower end for attachment of a load-receiving member. Operation of the lifting beam is implemented by a drive in the form of a cylinder which is actuated by a pressure medium and securely fixed to the longitudinal member. The cylinder has a movable part a piston which is connected to the lifting beam.
This lifting apparatus suffers shortcomings because of the complexity to suit the lifting apparatus to different operating conditions.
It would therefore be desirable and advantageous to provide an improved lifting apparatus for realizing a rectilinear movement of a handling device, which obviates prior art shortcomings and is easy to suit to different operating situation, while being producible in almost any desired length and adaptable to a wide range of different length requirements, such as, e.g., to the length of the lifting beam and to the fastening height of the lifting apparatus.
According to one aspect of the present invention, a lifting apparatus for implementing a rectilinear movement of a handling device, includes a pair of longitudinal members arranged in parallel relationship in a common plane at formation of a space therebetween and securable to a stationary or movable carrying unit; at least one connecting element rigidly interconnecting the longitudinal members; a drive mechanism; a lifting beam movable by the drive mechanism longitudinally along the longitudinal members and having attached thereon, directly or indirectly, the handling device; and a guide rail extending parallel to and supporting the lifting beam, wherein the guide rail is received in guide elements, arranged at a distance behind one another, for displacement in longitudinal direction in a freely running manner as the lifting beam is moved by the drive mechanism, wherein the guide elements are arranged in the space between the longitudinal members and secured to the connecting element, wherein the longitudinal members and the lifting beam are formed with longitudinal grooves for engagement of sliding blocks so that the connecting element, the drive mechanism and the carrying unit are securable to the longitudinal members in any desired longitudinal position, and the guide rail is securable to the lifting beam in any desired longitudinal position.
The present invention resolves prior art problems by providing a lifting apparatus in which the essential length-determining elements, i.e., the lifting beam and the two parallel longitudinal members, are provided with continuous longitudinal grooves for cooperation with fasteners that engage behind the grooves. As a consequence, the lifting beam and the longitudinal members may be made from aluminum profiles of square or rectangular cross section, which have been produced preferably through extrusion. Aluminum profiles can be cut to size in any desired length and can be produced very cost-effectively. The provision of longitudinal grooves allows the user to suit the position of the lifting beam to the situation at hand before fastening. Furthermore, the longitudinal members may be mounted to a trolley at a desired height, without need for any additional measures. In case of changes to the work area, the height can thus be altered to new height conditions (trolley/handling device spacing) in an easy manner by few manipulations.
According to another feature of the present invention, the guide elements may include a recirculating bearing, thereby allowing easy guidance of the lifting beam at little amount of play.
According to another feature of the present invention, the connecting element is may be provided by a metal plate which is easy to produce.
According to another feature of the present invention, the drive mechanism may be implemented by a cable balancer having a cable secured to a lower end of the lifting beam. This configuration is suitable, in particular, for a vertical lifting beam which, by way of their own weight move automatically downward into a position predetermined by the cable length.
The handling device, which may be a load-receiving member or a tool, may be fastened, for example, to an intermediate attachment element which is a horizontal member designed as an aluminum profile. Suitably, the attachment element is mounted to the lifting beam via a load-moment support.
According to another feature of the present invention, the longitudinal members may have stop members secured by sliding blocks for limiting a lifting path of the lifting beam.